The popularity of wireless telephony has grown at an exponential rate over the past several years. As an increasing number of people use wireless telephones as a substitute for traditional wireline telephones, telecommunications service providers must be ready to seamlessly provide service features and facilities normally associated with wireline service to the users of wireless telephony services.
One important and government mandated service required in both wireline and wireless telephony is public safety administration services (also known as emergency or "911" services). The hallmark of 911 service is the ability of the emergency service personnel to view the address of a distressed caller while the call is ongoing. In wireline applications, 911 service is easily administered because the caller uses equipment associated with a fixed address or location. Indeed, the caller's address aids 911 personnel in identifying appropriate emergency services units to respond to the distressed caller's request.
Wireless telephony poses an entirely new challenge for emergency service administration. Due to the very nature of wireless telephony, a distressed caller may be using a mobile unit in any geographic region where wireless service is provided. The challenge for emergency personnel and wireless service providers is to pinpoint the location of a distressed caller so that appropriate emergency service personnel may be dispatched.
Navigation systems, such as global positioning systems, have greatly enhanced the ability of emergency personnel to locate a distressed user of a mobile unit. Indeed, the current state of navigation system art allows the identification of an object within an area of one hundred (100) meters in an east-west dimension and one hundred fifty six (156) meters in a north-south dimension. Even with the impressive accuracy of existing navigation systems, there are situations in which emergency personnel have problems physically reaching a distressed user of a mobile unit. For example, if the distressed mobile unit user is in a high-rise building or a large office complex, the navigation system's resolution falls short of the desired goal of actually identifying the physical location of a distressed caller.